---
title: CustomerMergeOverrideFields - GraphQL Admin
description: >-
  The input fields to override default customer merge rules. These overrides are
  field-specific; they don't

  provide a general way to force a particular customer ID to survive the merge.
api_version: 2026-10
source_url:
  html: >-
    https://shopify.dev/docs/api/admin-graphql/latest/input-objects/CustomerMergeOverrideFields
  md: >-
    https://shopify.dev/docs/api/admin-graphql/latest/input-objects/CustomerMergeOverrideFields.md
api_name: admin
api_type: graphql
type: input-object
---

# Customer​Merge​Override​Fields

input\_object

The input fields to override default customer merge rules. These overrides are field-specific; they don't provide a general way to force a particular customer ID to survive the merge.

## Fields

* customer​Id​Of​Default​Address​To​Keep

  [ID](https://shopify.dev/docs/api/admin-graphql/latest/scalars/ID)

  The ID of the customer whose default address will be kept.

* customer​Id​Of​Email​To​Keep

  [ID](https://shopify.dev/docs/api/admin-graphql/latest/scalars/ID)

  The ID of the customer whose email will be kept. The selected customer must have an email address. When this field is provided and valid, the selected customer is also the resulting customer after the merge.

* customer​Id​Of​First​Name​To​Keep

  [ID](https://shopify.dev/docs/api/admin-graphql/latest/scalars/ID)

  The ID of the customer whose first name will be kept.

* customer​Id​Of​Last​Name​To​Keep

  [ID](https://shopify.dev/docs/api/admin-graphql/latest/scalars/ID)

  The ID of the customer whose last name will be kept.

* customer​Id​Of​Phone​Number​To​Keep

  [ID](https://shopify.dev/docs/api/admin-graphql/latest/scalars/ID)

  The ID of the customer whose phone number will be kept.

* note

  [String](https://shopify.dev/docs/api/admin-graphql/latest/scalars/String)

  The note to keep.

* tags

  [\[String!\]](https://shopify.dev/docs/api/admin-graphql/latest/scalars/String)

  The tags to keep.

***

## Mutations using this input

* [customer​Merge.overrideFields](https://shopify.dev/docs/api/admin-graphql/latest/mutations/customerMerge#arguments-overrideFields)

  ARGUMENT

***

## Map

### Mutations using this input

* [customer​Merge.overrideFields](https://shopify.dev/docs/api/admin-graphql/latest/mutations/customerMerge#arguments-overrideFields)